Planetary Science Seminar fall-2019
Formation of Giant planets and the origin of their heavy elements
Oct. 10, 2019,
noon - 1 p.m.
3853 Slichter
Presented By:
Yasuhiro Hasegawa
JPL
The origin of Jovian planets in both the solar and extrasolar systems is still elusive. The recent significant progress of astronomical observations and NASA's Juno mission has opened up invaluable opportunities of answering to this long-standing problem. In this talk, I will explore the origin of the total heavy-element content of Jovian planets. Making use of the existing semi-analytical formulae of accretion rates of pebbles and planetesimals, I will show that the total heavy elements inferred both for Jupiter and giant exoplanets would originate from solid accretion at the final stage of giant planet formation. In the stage, proto-jovian planets accrete solids from gapped planetesimal disks, and gas accretion is limited by disk evolution. I will also apply this finding to identifying the main formation site of these planets, and show that the plausible region may locate at r > 0.6 au, implying the importance of planetary migration. The combination of these efforts may enable us to move towards a comprehensive understanding of giant planet formation.